Reproductive system is a system of sex-organs which works in a coordinated way for the purpose of sexual reproduction which is vital only for continuity of species and not vital for life. Main male reproductive organ, testis produces male gamete (sperm) and main female reproductive organ, ovary produces ovum, which fuse to form a zygote. They also produce sex hormones which are necessary for development of sexual characters. Urine is produced by kidney but passes through urethra in penis. Penis is also a copulatory organ, which transfers sperms to vagina.